content: /**
   * Copyright (c) 2016-present, RxJava Contributors.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package io.reactivex.observable;
  
  import static io.reactivex.observable.Observable.combineLatest;
  
  import org.junit.*;
  
  import io.reactivex.common.functions.*;
  import io.reactivex.observable.ObservableCovarianceTest.*;
  import io.reactivex.observable.subjects.BehaviorSubject;
  
  public class ObservableCombineLatestTests {
      /**
       * This won't compile if super/extends isn't done correctly on generics.
       */
      @Test
      public void testCovarianceOfCombineLatest() {
          Observable<HorrorMovie> horrors = Observable.just(new HorrorMovie());
          Observable<CoolRating> ratings = Observable.just(new CoolRating());
  
          Observable.<Movie, CoolRating, Result> combineLatest(horrors, ratings, combine).blockingForEach(action);
          Observable.<Movie, CoolRating, Result> combineLatest(horrors, ratings, combine).blockingForEach(action);
          Observable.<Media, Rating, ExtendedResult> combineLatest(horrors, ratings, combine).blockingForEach(extendedAction);
          Observable.<Media, Rating, Result> combineLatest(horrors, ratings, combine).blockingForEach(action);
          Observable.<Media, Rating, ExtendedResult> combineLatest(horrors, ratings, combine).blockingForEach(action);
  
          Observable.<Movie, CoolRating, Result> combineLatest(horrors, ratings, combine);
      }
  
      BiFunction<Media, Rating, ExtendedResult> combine = new BiFunction<Media, Rating, ExtendedResult>() {
          @Override
          public ExtendedResult apply(Media m, Rating r) {
              return new ExtendedResult();
          }
      };
  
      Consumer<Result> action = new Consumer<Result>() {
          @Override
          public void accept(Result t1) {
              System.out.println("Result: " + t1);
          }
      };
  
      Consumer<ExtendedResult> extendedAction = new Consumer<ExtendedResult>() {
          @Override
          public void accept(ExtendedResult t1) {
              System.out.println("Result: " + t1);
          }
      };
  
      @Ignore("No longer allowed")
      @Test
      public void testNullEmitting() throws Exception {
          // FIXME this is no longer allowed
          Observable<Boolean> nullObservable = BehaviorSubject.createDefault((Boolean) null);
          Observable<Boolean> nonNullObservable = BehaviorSubject.createDefault(true);
          Observable<Boolean> combined =
                  combineLatest(nullObservable, nonNullObservable, new BiFunction<Boolean, Boolean, Boolean>() {
                      @Override
                      public Boolean apply(Boolean bool1, Boolean bool2) {
                          return bool1 == null ? null : bool2;
                      }
                  });
          combined.subscribe(new Consumer<Boolean>() {
              @Override
              public void accept(Boolean aBoolean) {
                  Assert.assertNull(aBoolean);
              }
          });
      }
  }
  